Here’s a quick look at some of the things you can do with the Bus Pirate. Bus Pirate is an open source hacker multi-tool that talks to electronic stuff. It’s a versatile little gadget that plugs into your computer via USB and can interface with a whole bunch of different chip to chip protocols as well as taking voltage and frequency readings.
We’ve got a pile of old home routers in the MakerSpace so I cracked a few open to see what’s inside them. This one is an EE Brightbox which has been pretty well investigated already but the same technique works on all sorts of different hardware. One of the first things I noticed was an exposed serial port. I soldered on some header pins and connected to it in UART mode and it spat out a boot log showing it was running Linux and a lot of other potentially useful information. It also allowed me to change some of the options that would be set in the factory such as the serial number and MAC address.
Another fun thing it can do is read/write to flash memory on devices. I had a particularly photogenic example but my friend borrowed it while working on his dissertation so I don’t have a photo of it here. We soldered wires directly to the legs of an SPI chip like this one and ran a tool called flashrom which saved the contents to my laptop. The next step would be to run binwalk on it to extract the contents (in this case a Linux file system) and potentially find some vulnerability in it.
Here I used it to reprogram the lights on my 44con badge. The badge (from a computer security conference) has an ATtiny85 chip which is pretty similar to the ATmega that controls an Arduino. All I had to do was hook the right pins up and changed a few options in the Arduino IDE to use the Bus Pirate as the programmer.
It can also be used for debugging electronics projects by operating as a logic analyser or oscilloscope but it’s got quite a slow sample rate so it’s not ideal for that. If you want to play with it give me a shout during one of our Monday open evenings.